Method of examining x-ray films and the like and an examination cabinet for such film examination

ABSTRACT

When examining X-ray film in an examination cabinet, the films are advanced consecutively in a horizontal direction from a magazine attached or capable of being attached to one side of the cabinet. The films are placed against each other in the magazine and are removed therefrom at least partly by a feed roller. Oppositely angled parts located on an endless transporting device engage the lower edges of respective films. After being examined, the films are delivered to a further magazine located on the other side of the cabinet. Located at one end of the cabinet is a ramp, on which is mounted a plurality of diodes which enable the various operations carried out in conjunction with the examination of X-ray film to be automated. The cabinet, magazine and transporting device can be constructed in the form of a module system. One of two modules can be placed above the other, and the modules can be adjusted angularly in relation to each other. The invention also relates to the examination cabinet itself.

TECHNICAL FIELD

The present invention relates to a method of examining X-ray film andlike image receptors in an examination cabinet of the kind whichincludes an illuminated surface and in which separate films are advancedconsecutively in front of the illuminated surface and stopped in anexamination position.

The invention can be applied to other types of receptors than forX-rays, such as film from image plates, ultra-examinations andMR-examinations for instance.

The invention also relates to X-ray film examining cabinets and cabinetsfor examining like film.

BACKGROUND PRIOR ART

Conventionally, X-ray film is examined and studied for diagnosticpurposes by hanging the film manually in front of an illuminated surfacein an illuminated cabinet. When a large number of films are to beexamined, the films are normally hung on a plurality of transparent filmframes which are positioned in front of the illuminated surface with theaid of a motor-driven conveyor mechanism.

The film frames are normally stored in magazines which may either bestationary or mobile. Moble magazines enable the frames to be conveyedbetween different film examining cabinets when the need arises.

Alternatively, and instead of film frame magazines, there may be usedtransparent plastic belts which are capable of being rolled in front ofthe illuminated surface in a horizontal or vertical direction.

The films are normally of a standard size, with a smallest dimension of13×18 cm and a largest dimension of 35×43 cm. The film accommodatingsurface of the magazined film frames will normally be 150×50 cm in size.

A film frame magazine for use in an examination cabinet will normallyhave a capacity of 100-110 films. Some magazines, however, willaccommodate 200-300 films having a maximum dimension of 35×43 cm.

When considering that the film frame requires a surface dimension whichis about four times as large as the maximum film dimension and thatabout 75 films, each having a standard thickness of about 0.2 mm, can bepacked depthwise within the standard or normal space between two filmframes in a magazine, it will be seen that a film frame magazine demandsthe provision of much more space and the handling or manipulation ofmuch heavier weight than when handling loose films. Such handlingoccurs, for instance, in the case of mobile routines in which the filmsare first hung in a cabinet for pre-examination purposes and thentransported to another examination cabinet, where the films are examinedand studied in greater detail.

The same also applies to the aforementioned plastic belts, which may beendless belts but which are often wound up in rolls for mobiletransportation. In this respect, examination of the films can be besetwith difficulties resulting from different types of operationaldisturbances, causing the films to be even less accessible than whenstored in a frame magazine. This can have disastrous results, forinstance, in catastrophic situations, or may require re-takes to bemade, subjecting the patient to an increased dosage of radiation. Thefilms are also easily deformed when rolling up the belts.

It is also known in the case of image projectors and like apparatuses toadvance images sequentially from an image discharging magazine to animage examining or viewing position, and from there to an imagereceiving magazine.

One example of such apparatus is described and illustrated in U.S. Pat.No. 1,002,078 (Paoli). This publication describes a magic lantern in theform of a slide projector having a slide change mechanism which iseffective in changing slides in a manner such that the images thereonwill merge into each other without any abrupt demarcation therebetween.

Another known apparatus of the aforesaid kind is described andillustrated in U.S. Pat. No. 4,331,398 (Kawarada et al.). Thispublication teaches a device for transporting a plurality of slide filmmounts in either direction between a pair of magazines in a slideprojector with the aid of endless drive belts which extend over an openend of each magazine in close contact therewith and with steppedshoulder portions formed in the belt surface facing the open ends of themagazines.

U.S. Pat. No. 4,368,964 (Carlson) teaches a similar film-slide projectorhaving an automatic slide changer and stationary magazine on each sideof the projector, the respective slide magazines having a feed anddischarge opening for slide frames which is located in the focal planeof the slide projector.

British publication 1 175 454 (Itek) describes a projector having atransparent film carrier mechanism which includes a supporting elementand a positioning device for selective movement of the supportingelement longitudinally or perpendicularly to the optical axis.

None of these known apparatuses, however, describes or illustrates theviewing of X-ray film, and consequently none discusses the problemsparticularly associated therewith. For instance, in all of the knownapparatuses all films or slides to be viewed are of the same size,whereas films used for X-ray diagnosis normally vary in size, and thefilm sizes are considerably larger than the size of slides used in slideprojectors.

Further examples of standard techniques German publications 2 039 208(Agfa. Gevaert), 2 061 828 (Saab-Scania), 2 119 373 (Kalle) and 3 439923 (Abels), and European publication 0 107 043 (MAP).

None of these publications, however, disclose any solution to theparticular problems associated with X-ray diagnosis outlined above.

OBJECTS OF THE INVENTION

The objects of the present invention are to eliminate theabove-mentioned and other drawbacks encountered with known filmexamining methods and film examining cabinets, to provide for morereliable and less space-consuming storage of X-ray films; to facilitatethe work of the person studying the film and of other personnel,including the handling of heavy weights in conjunction with X-raydiagnostic procedures, and to enable the X-ray films for examination tobe identified and checked positively, so that it is certain that a givenX-ray image corresponds to a given patient's admission note.

One particular object of the invention is to shorten the film handlingtimes in connection with the examination and study of X-ray films, sothat the greater part of the overall time can be concentrated on thetask of actually examining the films.

SUMMARY OF THE INVENTION

These and other objects of the invention are fulfilled by means of theinventive method, which is mainly characterized by introducing the filmsto be examined, one against the other, into a magazine located orlocateable on one side of an illuminated surface, and advancing thefilms horizontally to the film examining position with the aid of atransporting device having means for gripping the films, preferably inan edge region thereof, and then preferably in the region of the bottomedge.

By inserting the films in this way into a magazine having externaldimensions which slightly exceed the largest standard film size of 35×43cm and which has a thickness corresponding generally to the thickness ofthe examination cabinet, it is possible to store about 400 films. Thisrepresents a considerable saving in space when compared with knownmagazine storage. The manual work involved in mounting the films inframes is also eliminated. Since the weight of such frames is quiteconsiderable, it will be appreciated that their absence will greatlysimplify the work involved in, for instance, transporting or conveyingthe films between different examination cabinets.

The magazine is also capable of storing mutually adjacent films ofvarying sizes without detrimental effect on the function of theexamination cabinet. The X-ray images or films of a patient will oftenbe of mutually different size, and the invention will consequentlyenable these films or images to be stored mutually adjacent one anotherand fed-out sequentially from the magazine to the illuminated surface.The size of the illuminated surface is suitably such as to enable anumber of images to be studied simultaneously.

When practicing the inventive method, the gripping means will preferablybe arranged to deliver films transported along the illuminated surfaceto a second magazine which is located on the other side of the surface,or capable of being located on the other side.

This second magazine may be used optionally to store the films uponcompletion of the examination or study.

The second magazine may, if desired, have the same configuration as thefirst magazine and may be mounted on the infeed side of the illuminatedsurface, subsequent to reversing the pack of film, to enable the filmsconcerned to be re-examined.

Alternatively, all of the films in the second magazine may be removedtherefrom and transferred, suitably packed, to a film storage location,for instance.

When both magazines are rigidly mounted on the illuminated cabinet, thefilms are inserted into the first magazine before commencing theexamination or study.

The film transporting device is preferably movable in both directions,so that the device can be moved backwards when so desired.

In accordance with one preferred embodiment of the invention, filmtransportation is facilitated by moving the films into the gripping orengagement position by means of a rotatable feed roller which isarranged on one side edge of the magazine and which is preferablysynchronized with the transporting device, so that the peripheral speedof the feed roller corresponds to the speed of the film transportingdevice.

The inventive method can be further developed in various respects, forthe purpose of increasing reliability and of facilitating the work ofthe person examining the film. Thus, the film format is preferablydetermined, e.g. optoelectrically, as the film is transported to theexamination position, and the resultant values are utilized, through amicrocomputer, for causing the film to stop automatically in apre-determined film examination position and to obtain automatic lightcollimation with the aid of movable light baffles or curtains.

To this end, there may be provided, adjacent the outfeed slot of themagazine, a ramp having arranged thereon a plurality of diodes for usein determining the format of the film concerned. The diodes may beprovided in numbers corresponding to the number of standard film sizesused, enabling the size of each film discharged from the magazine to bereadily determined. The system microcomputer is also supplied withvalues corresponding to the prevailing speed of the film transportingdevice and is able to produce, on the basis of these values, the controlsignals required for putting the aforesaid functions into effect.

Correspondingly, the diode ramp may also have arranged thereon one ormore diodes which are effective in detecting the density of the film,i.e., the degree of blackening. This information is used, for instance,to control the light intensity of the cabinet light source. If theintensity of the light entering the cabinet is maintained at an optimal,even level in this way, the person examining the film will not becometired as a result of needing to, inter alia, adapt his sight to shiftinglight intensities, thereby enabling a diagnosis to be made more easilyand more positively.

The inventive method also enables forward feed of the film to becombined with reading of text or bar codes, e.g. with the aid of anOCR-unit (Optical Character Reader) during passage of the film betweenmagazine and examining position.

When applying the method in practice, preferably, two examinationcabinets of module construction are used, together with associatedmagazines and film transporting devices, with one cabinet placed abovethe other, preferably with the possibility of adjusting the angle of theseparate modules and/or displacing the upper module to a position infront of the lower module.

This arrangement of two modules enables a plurality of X-ray films to bestudied simultaneously and facilitates comparison between individualimages or series of images with mutual selective combinations or withsynchronization between the two modules. This will afford a reliableancillary for reaching a diagnosis or for instruction purposes.

Displacement of the upper module to a position in front of the lowermodule enables close-up studies to be made, if so desired.

In order to facilitate close study of the X-ray films, at least a partof the working table can be displaced horizontally and/or swung to avertical position, in which a close study of the film located in theexamination position can be made.

It is also possible within the concept of the invention to measure theheight or thickness of the film pack, so as to be able to calculate andindicate the utilized or free capacity of the film magazine with thepossibility of calibrating the detecting means, e.g., via a suitablepotentiometer capable of being set for mutually different filmthicknesses.

For instruction or demonstration purposes, it is also possible toproject single images or a multiple set of images onto one or moreTV-monitors. To this end, there can be used a stationarily or movablymounted video camera located in a suitable position in front of theilluminated surface. All of the films transported will, therefore, passthe camera without needing to take down the film or films to beprojected onto the TV-monitor and place the film or films onto anilluminated surface intended for the camera and then re-hanging the filmor films.

In accordance with another aspect, the invention also relates to acabinet for examining or studying X-ray film and like image receptors.

An exemplifying embodiment of the invention will now be described inmore detail with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an inventive examination cabinetprovided with exchangeable film magazines and a control panel.

FIG. 2 is a sectional view taken on the line II--II in FIG. 1 andillustrates an end wheel of the film transporting device, showing theengagement or gripping means in a position for engagement with a filmfed from the magazine.

FIG. 3 is a sectional view taken on the line III--III in FIG. 1, andillustrates the engagement or gripping means of the film transportingdevice during transportation of a film.

FIG. 4 is a side view of part of the examination cabinet illustrated inFIG. 1, and shows the arrangement of a horizontally displaceable tabletop.

FIG. 5 is a side view of an embodiment which is a slightly modifiedversion of the embodiment illustrated in FIGS. 1 and 4 and whichcomprises two examination cabinets in the form of module units placedone on top of the other, with the possibility of adjusting the relativeangle between the respective module units.

FIG. 6 illustrates an alternative arrangement of the units illustratedin FIG. 5, in which the upper unit can be displaced to a position infront of the lower unit, in order to enable a close-up study to be madeof the film concerned.

DESCRIPTION OF PREFERRED EMBODIMENTS

An X-ray film examination cabinet comprises a module unit, generallyreferenced 1, having a central illuminated cabinet, generally referenced2, which is flanked on both sides thereof by a respective X-ray filmmagazine, generally referenced 3.

The module unit 1 is supported on a stand 4, which also supports, infront of the cabinet, a working table 5 having a part 5a which can beswung down to a vertical position.

The illuminated cabinet 2 comprises a front, mat glass plate 6, in frontof which there extend vertically adjustable guide devices in the form ofnylon strips or bands 7 which are effective in guiding and retainingX-ray films 12 fed from one of the magazines 3. The cabinet 2 alsoincludes a light source, in the form of one or more vapour dischargelamps 8 of adjustable light intensity.

The cabinet has mounted therein screening devices in the form of blinds9, which can be moved from the sides of the cabinet towards the centrethereof, and a centrally located blind 10, which can be moved verticallyup and down.

The X-ray films 12 are inserted in the magazine 3 in mutually contiguousrelationship, the dimensions of the magazine slightly exceeding thedimensions of the largest standard film format, i.e., a format of 35×43cm. Charging of the magazine can be effected at some other location,e.g. at the place where the films are developed and pre-examined,whereafter the charged magazine is transported to the cabinet andconnected thereto.

A magazine having a thickness or depth which corresponds to thethickness or depth of the cabinet is able to accommodate about 400 filmsof varying format. Located on the side surface of the magazine facingtowards the cabinet is an outfeed opening while arranged adjacent thisopening is a film feed roller 13, which is driven by a motor 14 andengages the uppermost film in the magazine. The film is advanced someshort distance by the feed roller, After which the film transportfunction is taken over by a film transporting device located beneath thecabinet, as hereinafter described.

The magazine 3 is provided with a sprung bottom plate, the resiliency ofwhich ensures that the uppermost film is urged against the feed roller13 irrespective of the number of films 12 remaining in the magazine.

The film transporting device includes an endless belt 20 which extendsover rollers 21 journalled at respective ends of the cabinet.

The film transporting device is driven, via a gear-box, by the samedrive source 14 as that which drives the feed roller 13, such as to bedriven synchronously therewith, i.e. so that the speed of the transportbelt 20 will correspond to the peripheral speed of the roller 13.

The transport belt 20 is made of an elastic material and includesoppositely angled parts 20a, which function as gripping means when apart of the belt 20 passes an end roller 21 provided with a V-shapedprofile, whereupon oppositely and downwardly angled parts 20b of thebelt are squeezed together such as to form an opening between the twoupper, oppositely positioned parts 20a. The roller 13 is operative infeeding the lower edge of a film 12 into this opening and when the beltpart in question subsequently leaves the roller 21, the parts 20a aremoved together in gripping engagement with the bottom edge of the film12, so that the film will be carried by the belt to a film examiningposition in front of the illuminated surface 6, where the belt isstopped to enable the film to be examined or studied.

Located on one side of the illuminated cabinet 2, adjacent the magazine3, is a vertical diode ramp 26 having provided thereon a plurality ofdiodes 27 for determining the format of respective films, and one ormore further diodes 28 for detecting the density or degree of blackeningof the film. These diodes are intended to control the film transportingdevice 13, 14, 20, 21, the horizontally movable blinds 9 and thevertical movable blind 10, with the aid of a microcomputer, such thatthe images will take a correct position for examination on the screenand to also obtain a suitable screening, for instance to screen outlight which might be distracting to the person carrying out theexamination.

The diodes 27 also regulate the intensity of the light emitted by thelight sources 8, such as to illuminate, in an optimum manner, thoseparts of the images to be studied. The ramp 26 also has mounted thereonan OCR-unit for reading the bar codes located on the lower part of thefilm, when such bar codes are present, therewith enabling the X-rayfilms to be reliably identified.

The film transporting device delivers films which have passed theilluminated surface 6 to a further magazine 3 located on the other sideof the cabinet, this further magazine being similar to thefirstmentioned magazine. When filled, this further magazine can bedetached from the cabinet and replaced with an empty magazine.

Subsequent to emptying the magazine of film it may be refilled with anew batch of X-ray films and, subsequent to being turned 180°, used asan infeed magazine on the other side of the cabinet.

Alternatively, the infeed and outfeed magazines 3 may be fixedlyattached to respective ends of the cabinet, in which case one magazineis filled with film prior to a film examining procedure and the other isemptied of film subsequent to said procedure.

As indicated in chain lines in FIG. 1, the central part 5a of the table5 can be swung down to a vertical position. Located on the table 5 is acontrol panel 29, by means of which the film examiner manipulates thefilm conveying device 20 and carries out other requisite operations.

As illustrated in FIG. 4, the table 5 may alternatively or additionallybe displaceable horizontally in a manner which will enable close-upstudies of films to be made when necessary.

FIG. 5 illustrates schematically an embodiment of the invention whichcomprises two module units 1, each of which includes a respective filmexamination cabinet and which are placed one above the other and includea facility which will enable the cabinets to be angled in relation toone another, such as to bring respective cabinets to the best viewing orexamining position. The various components of the module units, such asthe film transporting devices, have not been shown for the sake ofsimplicity.

FIG. 6 illustrates schematically an alternative arrangement in which theupper module unit can be displaced to a position in front of the lowerunit. This arrangement enables images or films on the upper module to beexamined in the same position and at the same angle of inclination asthe lower module, thereby providing for more positive diagnosis.

This movement of the module can either be effected manually, e.g. withthe aid of a counterbalance arrangement or with the aid of a motor.

The aforesaid provision of an OCR-unit in conjunction with the dioderamp 26 will enable text or different bar code systems to be read-off,such codes and text being used to an increasing extent within hospitaladministration, for the purpose of registering patients and forproviding immediate access to the medical history of a patient withoutneeding to search manually through a conventional file system.

Thus, the X-ray films of a particular patient can be automaticallycollected and moved to a position in front of the illuminated surface 6by deciphering the code in a computer at the place where the film is tobe examined. Conversely, the requisite information relating to aparticular patient can be extracted from a computer located at theworking site, by deciphering the code at the same time as the filmconcerned is fed from the magazine 3.

In addition, the motor-driven film conveying device 20, 21 willpreferably be adapted for manual drive, e.g. by mounting a crank on theshaft of the drive motor 14 of the feed roller 13, this crank at thesame time enabling the transporting device 20 to be drivensynchronously.

This arrangement will reduce the risk of time wasting in the event of anoperational breakdown, for example, in a hospital emergency localitywhere a delay in making a diagnosis because film is not available mayhave disastrous results to the patient, in the worst case requiring theX-rays to be retaken.

As an alternative, the use of purely manually driven systems, i.e.systems not equipped with drive motors and associated automaticmechanisms, is conceivable in X-ray centres in which the equipment ingeneral conforms, for instance, with the basic radiographic systemrecommended by WHO for developing countries.

One particular advantage afforded by the invention in comparison withknown techniques in which the films are hung in frames is that the needto re-hang films is obviated, i.e. the task of removing examined filmsfrom the frames and hanging new films therein is no longer necessary.The present invention also provides a significant simplification whendesiring to supplement a batch or array of sorted films with additionalfilms or when it is desired to remove certain films from a set of filmslocated, for instance, in a magazine.

It will be understood that the aforedescribed film examination methodand cabinet can be modified within the scope of the following claims.

I claim:
 1. In a method of examining X-ray film comprising the steps ofproviding an examination cabinet which includes an illuminated surface,advancing separate films consecutively in front of the illuminatedsurface, and stopping each of said separate films in a film examiningposition, the steps of:introducing separate films to be examined, oneagainst the other, into a magazine which is attachable to one side ofthe illuminated surface; providing a transporting device for advancingsaid separate films from said magazine, the transporting deviceincluding a horizontally movable part with means for releasably grippingsaid separate films; moving said means for releasably gripping intocontact with opposite surfaces of one of the separate films only in anedge region thereof when the one of the separate films is at leastpartly located in front of the illuminated surface; and moving saidmeans for releasably gripping out of contact with said opposite surfacesof the one of the separate films after it has been examined.
 2. A methodaccording to claim 1, and further comprising the step of depositingfilms in a further magazine which is attachable to the other side ofsaid surface.
 3. A method according to claim 1, and further comprisingthe step of advancing the separate films to the means for releasablygripping by a rotatable feed roller located adjacent one side edge ofthe magazine by driving the feed roller at a speed which corresponds tothe speed at which the separate films are advanced.
 4. A methodaccording to claim 1, and further comprising the step of providing anadditional examination cabinet of modular construction, together withassociated magazines and transporting devices, above the examinationcabinet, said additional examination cabinet being capable of makingangular adjustments.
 5. A method according to claim 1, and furthercomprising the step of displacing at least part of a working tablehorizontally by swinging said part to a vertical position to enable aclose-up study to be made of a film located in the examining position.6. An examination unit for X-ray films comprising:a stand having a worktable for a film examiner, a cabinet equipped with a light source andhaving a mat glass surface illuminated by said light source, a magazineattachable to the cabinet for receiving and supplying X-ray films to beexamined, said magazine accommodating the X-ray films one againstanother and being attachable to one side of the cabinet, and atransporting device for advancing individual X-ray films consecutivelyfrom the magazine to the illuminated mat glass surface, the transportingdevice including a part which is horizontally movable, said part whichis horizontally movable including means for releasably gripping theX-ray films by moving into and out of contact with opposite surfaces ofthe X-ray films only in a region near edge surfaces thereof and onlywhen the X-ray films to be examined are located in front of the matglass surface.
 7. A cabinet according to claim 6, and further comprisinga further magazine attachable to the cabinet, the transporting devicedelivering films which have been transported along said illuminated matglass surface to said further magazine.
 8. A cabinet according to claim7, characterized in that each magazine is substantially identical to theother and can be exchanged for the other.
 9. A cabinet according toclaim 6, and further comprising a feed roller arranged along a side edgeof the magazine located adjacent the cabinet, said feed roller beingeffective in advancing the films from a storage position in the magazineto a position for engagement with the means for releasably gripping saidfilms, said feed roller having a peripheral speed corresponding to thespeed at which the individual films are advanced.
 10. A cabinetaccording to claim 6, and further comprising strip-like film guidesextending horizontally along the illuminated mat glass surface.
 11. Anexamination cabinet for X-ray films comprising:a stand having a worktable for a film examiner, a cabinet equipped with a light source andhaving a mat glass surface illuminated by said light source, a magazineattachable to the cabinet for receiving X-ray films to be examined, atransporting device for advancing individual X-ray films consecutivelyfrom the magazine to the illuminated mat glass surface, the magazineaccommodating the X-ray films one against the other and being attachableto one side of the cabinet, the transporting device being horizontallymovable and including means for releasably gripping the films in aregion of an edge surface thereof, an endless movable belt, and terminalrollers beneath the cabinet about which the endless movable beltextends, the movable belt including elastic parts functioning as saidmeans for releasably gripping, said elastic parts opening upon passageof the belt over said terminal rollers so as to subsequently closearound the lower edge of a film fed from the magazine.
 12. Anexamination cabinet for X-ray films comprising:a stand having a worktable for a film examiner, a cabinet equipped with a light source andhaving a mat glass surface illuminated by said light source, a magazineattachable to the cabinet for receiving X-ray films to be examined, anda transporting device for advancing individual X-ray films consecutivelyfrom the magazine to the illuminated mat glass surface, the magazineaccommodating the X-ray films one against the other and being attachableto one side of the cabinet, the transporting device being horizontallymovable and including (1) means for releasably gripping the films in aregion of an edge surface thereof at least partly formed by an endlessmovable belt, and (2) terminal rollers beneath the cabinet about whichthe endless movable belt extends, the means for releasably gripping thefilms opening and closing around a lower edge of a film fed from themagazine at approximately a right angle relative to a direction in whichthe film is fed.